The invention pertains to fonts used during the plugging of bowling ball finger holes.
Ten pin bowling balls are grasped by the bowler through the use of finger holes. Usually, three finger holes are employed for receiving the thumb and two middle fingers, but two finger hole balls are also used. As the spacing and the diameter of the finger holes are very important with respect to the "feel", comfort and control of the use of the ball, the bowler often desires to modify the finger hole spacing or diameter in order to improve his performance. Modification of a finger hole is achieved by filling the existing hole, or holes, with a plugging compound of a synthetic plastic material which hardens and firmly adheres within the finger hole to the ball. The hole is overfilled and the surface of the ball is machined to the desired spherical configuration, and new finger holes are drilled of the desired shape and at the desired location. Usually, in the redrilling of the finger holes, at least a portion of the plugging material is drilled in that the relocating, or resizing, of the hole is usually of a limited dimensional change.
The finger holes are plugged with a synthetic plastic resin material which is mixed with a catalyst and poured into the finger hole. The mixed plugging compound hardens and becomes integral with the ball. It is the practice to overfill the finger hole to insure that the finger hole is completely filled even though some shrinkage of the compound occurs whereby a truely spherical surface can be restored to the ball prior to redrilling. To overfill the finger hole it is necessary that the overfill be confined in that the consistency of the mixed plugging compound is quite viscous, comparable to syrup or heavy cream.
It has been the practice to confine the plugging compound overfill with a "dam" built around the finger hole by means of a moldable clay material. The usual practice is to manually form an annular ridge of clay on the ball surface around the hole to be filled, and this ridge forms a dam permitting the finger hole to be overfilled sufficiently to completely fill the finger hole.
After the plugging compound has hardened a router is placed upon the ball and routs away the "excess" plugging compound radially extending beyond the surface of the ball. During the routing operation the clay dam is also routed, if it is not first broken away, and removed from the ball. After the routing operation the new finger hole is drilled at the location, and of the diameter desired.
The aforementioned procedure is commonly employed in the plugging and reboring of bowling ball finger holes, and it will be appreciated that the manual forming of the clay dam about the finger hole is time consuming, and haphazard, and the effectiveness of the dam depends upon the skill of the builder. Ball hole plugging compound is expensive, and if a dam of too large a diameter is formed, plugging compound is wasted. If the dam is not formed "high" enough sufficient compound may not be placed in the hole and in the dam sufficient to fill the entire area to be resurfaced. Also, if the dam is not carefully constructed it will leak, and the clay material of the dam is abrasive enough to dull the router cutter over a period of time. Further, using a clay dam it is difficult to fill and plug more than one hole at a time when the holes are adjacent.